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Cultural traditions should not be lost, and yet because of lifestyle changes, reorganisation of family life and the influence of globalisation, the rich heritage of a country like Finland risks being forgotten. In this chapter, the author argues for ways to redress this situation by ensuring the transmission of traditions, cultural heritage and enculturation through early childhood education.

Art is a complex, multiform, fluid human activity that is subjugated to time-space-place contexts and dependent upon social representation and values. But what is it for? This introduction to the book Art in Diverse Social settings begins with a general characterization of Art as universal language. Unlike verbal language, art is primarily processed in the sensorial and emotional fields and only later rationally; unlike science, it does not aim at explaining or predicting the laws of the world's phenomena, instead it communicates by showing (in essence, it has an expressive meaning). In today's world, art became an accessible good and a valuable human creation because of this reappraisal of artistic practices; art is today expressive in domains such as politics, citizenship, economy, ethics, sustainability or public affairs.

The introduction to this edited book explains why it is focused on the role of art in today's diverse society. Art is part of the worldviews and mindsets from which it results and as a complex and ambiguous product of culture and perception, it must be understood from multiple perspectives. As such, this book includes in the first part seminal chapters with a theoretical scope, which highlight conceptual, contextual and cultural issues of contemporary art. The chapters in the second and third parts of the book are exemplary case studies, describing concrete intervention projects, which use some form of art or composed artistic expression as a medium for communication and intervention in the contexts of social and professional organizations, public spaces or the community. A summary of each chapter is provided and linked to the main goal of the book.

The purpose of this paper is to describe the behavior of different lead-free solders (95.5Sn3.8Ag0.7Cu, i.e. SAC387 and Sn7In4.1Ag0.5Cu, i.e. SAC-In) in thermomechanically loaded non-collapsible ball grid array (BGA) joints of a low-temperature co-fired ceramic (LTCC) module. The validity of a modified Engelmaier’s model was tested to verify its capability to predict the characteristic lifetime of an LTCC module assembly implementable in field applications.

Five printed wiring board (PWB) assemblies, each carrying eight LTCC modules, were fabricated and exposed to a temperature cycling test over a −40 to 125°C temperature range to determine the characteristic lifetimes of interconnections in the LTCC module/PWB assemblies. The failure mechanisms of the test assemblies were verified using scanning acoustic microscopy, scanning electron microscopy (SEM) and field emission SEM investigation. A stress-dependent Engelmaier’s model, adjusted for plastic-core solder ball (PCSB) BGA structures, was used to predict the characteristic lifetimes of the assemblies.

Depending on the joint configuration, characteristic lifetimes of up to 1,920 cycles were achieved in the thermal cycling testing. The results showed that intergranular (creep) failures occurred primarily only in the joints containing Sn7In4.1Ag0.5Cu solder. Other primary failure mechanisms (mixed transgranular/intergranular, separation of the intermetallic compound/solder interface and cracking in the interface between the ceramic and metallization) were observed in the other joint configurations. The modified Engelmaier’s model was found to predict the lifetime of interconnections with good accuracy. The results confirmed the superiority of SAC-In solder over SAC in terms of reliability, and also proved that an air cavity structure of the module, which enhances its radio frequency (RF) performance, did not degrade the reliability of the second-level interconnections of the test assemblies.

This paper shows the superiority of SAC-In solder over SAC387 solder in terms of reliability and verifies the applicability of the modified Engelmaier’s model as an accurate lifetime prediction method for PCSB BGA structures for the presented LTCC packages for RF/microwave telecommunication applications.